Genocide, crimes against humanity, war crimes, ethnic cleansing are terms which in recent years have entered common usage. The worst cases of these crimes seen in the Yugoslav secession conflict and the Rwandan slaughter resulted in attempts by the international legal community to initiate an international mechanism for establishing criminal accountability. In 1998, after many States signed the Rome Statute, it was expected that justice would prevail over state power and impunity be eliminated. However there is a serious question mark over the effectiveness of this process. That is the starting point for this collection. It is not an acclamatory collection that is meant to celebrate the undoubted advances of international criminal justice. The articles in the first part show the importance of comparative criminal law research to the development of international criminal justice, and in the second part they deal with the foundations, substantive and procedural aspects of international criminal law.